OK just one more time:
Suggest that when you take your phone into the Apple Store, you have the Apple person call your phone, put your phone on speaker so that they can understand the problem. What ever their fix, a replacement phone or a repaired one, have them call that phone with the IOS 13.3 and check. (Just do a New Phone setup for the test) If that works try IOS 13.3.1. (if that is what you want to run and test again by having them call your phone.) Do your restore and Test again. Yes I know it will take some time but Its Your $$$$.
Suggest that when you take your phone into the Apple Store, you have the Apple person call your phone, put your phone on speaker so that they can understand the problem. What ever their fix, a replacement phone or a repaired one, have them call that phone with the IOS 13.3 and check. (Just do a New Phone setup for the test) If that works try IOS 13.3.1. (if that is what you want to run and test again by having them call your phone.) Do your restore and Test again. Yes I know it will take some time but Its Your $$$$.